CN208758616U - Device for powder bed melting - Google Patents

Abstract

A kind of device for powder bed melting is provided, the apparatus may include the energy-beam source for generating energy beam and applies the energy beam so that dusty material melting carrys out the deflector based on object model creation 3D object.The system can also include the tokenizer for obtaining with making the dusty material melt related information.The tokenizer can be the sensor for the shape for measuring the object, the processor of the model based on physics for determining the object etc..The system can also include based on the determining compensator with the comparator of the difference of the object model and based on difference modification to the energy application of the dusty material of the information.For example, energy that can be applied in the middle increase in region (region of such as thicker powder bed) for requiring higher energy melt dusty material completely.

Description

Device for powder bed melting

Cross reference to related applications

This application claims entitled " ADDITIVE MANUFACTURING CONTROL SYSTEMS " and April 28 in 2017 The equity for the U.S. Patent Application No. 15/582,457 that day submits, by quoting whole be expressly incorporated herein.

Technical field

The disclosure is usually directed to increasing material manufacturing (Additive Manufacturing) system, and relates more specifically to increase material Control system in manufacture.

Background technique

Increasing material manufacturing (" the AM ") system for being also been described as 3-D print system can be produced with geometry complicated shape (packet Include certain shapes that creation is difficult or impossible to conventional fabrication processes) structure (referred to as building part (build piece)). AM system (such as powder bed melts (fusion) (PBF) system) successively creation building part.By deposited powder layer and by part powder End is exposed to energy beam to form each layer or each ' piece '.Energy beam is applied to the cross section weight with building part in the layer The melting range of the powder bed of conjunction.The powder of fusing is cooling and melts to form a piece of building part.The process can be repeated with shape The a piece of building part under, and so on.Each layer is all deposited on the top of preceding layer.The structure of generation is to match piecewise from the beginning The building part set.

It is expected that building part meets desired print parameters, all shapes as desired, desired density of material, desired machinery Characteristic etc..However, building part is often not in full conformity with desired print parameters.In some cases, lacking accordance can need Post-processing technology is wanted, sand milling, filing etc. construct the shape of part to correct, this will increase production cost.In some cases, Building part cannot be fixed and must abandon, this can reduce yield and dramatically increase production cost.

Utility model content

The many aspects of the device and method for the control system in AM hereinafter will be described more fully.

In in all fields, the device for powder bed melting may include: powder bed fusing system comprising generate energy Energy-beam source and the application energy beam for measuring beam are based on the deflection of three-dimensional (3-D) object of object model creation with melted powder material Device, the tokenizer for melting related information of acquisition and dusty material determine the difference with object model based on the information (variation) comparator and the compensator applied based on energy of the difference modification to dusty material.

In in all fields, the device for powder bed melting may include the instruction provided for printing 3-D object (should Instruct the data model based on 3-D object) adaptive controller；Powder bed based on instruction printing 3-D object melts system System；Be configured as sensing at least part of shape in printed 3-D object, the shape that will be sensed and reference figuration into Row is relatively to determine difference parameter and the feedback system based on the difference parameter more new command.

In in all fields, the method for powder bed melting may include generating energy beam, applying energy beam with melted powder Material come based on object model creation (3-D) object, acquisition information related with the melting of dusty material, based on the information determination Apply with the difference of object model and based on energy of the information modification to dusty material.

In in all fields, the method for powder bed melting may include that (this refers to for the instruction that provides for printing 3-D object Enable the data model based on 3-D object), based at least one in instruction printing 3-D object, the printed 3-D object of sensing Partial shape, the shape that will be sensed are compared to determine difference parameter and based on the difference parameter with reference figuration More new command.

According to described in detail below, other aspects will become easy to those skilled in the art it is clear that its In multiple embodiments only have shown and described by way of diagram.As the skilled person will recognize, this paper's is general Other and different embodiments can be had by reading, and in the case of not departing from the present disclosure, can be at various other aspects It modifies multiple details.Therefore, attached drawing and detailed description are substantially considered illustrative rather than restrictive.

Detailed description of the invention

The various aspects that will be presented by way of example, and not limitation in detailed description in attached drawing now, in which:

Figure 1A-D illustrates the example PBF system during the different operational phases.

Fig. 2 illustrates the side view of the exemplary sagging deflections in the PBF system that can result in the region pendency (overhang) Figure.

Fig. 3 illustrates the exemplary PBF device including closed-loop control.

Fig. 4 illustrates the exemplary PBF device including feedforward control.

Fig. 5 illustrates the exemplary operation of comparator.

Fig. 6 A-C is illustrated to be applied using example energy of the modified print command to powder bed.

Fig. 7 is the flow chart for illustrating the illustrative methods of the closed loop compensation for PBF system.

Fig. 8 A-C is illustrated to be applied using another exemplary energy of the modified print command to powder bed.

Fig. 9 is the flow chart for illustrating the illustrative methods of the feedforward compensation for PBF system.

Figure 10 A-E illustrates the exemplary PBF device with post-processing closed-loop control.

Figure 11 is the flow chart for illustrating the another exemplary method for the compensation of PBF system.

Specific embodiment

The various exemplary embodiments of concept disclosed herein are intended to provide below with reference to detailed description described in attached drawing Description, and being not intended to expression can only embodiment of the disclosure." exemplary " meaning of term used in the disclosure For " be used as example, example or explanation ", and be not necessarily to be construed as be relative to the other embodiments proposed in the disclosure It is preferred or advantageous.In order to provide the full and complete public affairs for having fully communicated concept and range to those skilled in the art It opens, detailed description includes detail.However, the disclosure can be practiced without these specific details.Certain In the case of, well-known structure and component can be shown in block diagram form, or are omitted entirely, to avoid this fuzzy entire public affairs Open each conception of species proposed.

The disclosure is for the control system in AM, such as powder bed melting (PBF).Current PBF system may be implemented Component geometric accuracy between ± 20 μm and ± 130 μm has R_a=25 μm of surface roughness.The achievable minimal wall of PBF Thickness is 150 μm.On the other hand, R may be implemented in electron-beam melting (EBM) system_a=40 μm and 700 μm of minimum wall thickness (MINI W.).When need When wanting smooth surface or submillimeter feature, this present challenges.Further, since such as discontinuous fusing carrier (melt Vectors), the phenomenon that " nodularization " effect, non-uniform powder distribution and endless running down, the component of certain 3-D printings Internal feature may be uneven.These phenomenons being capable of arrowhead precision, speed and handling capacity.

One of inhomogeneities is exposed to the powder of energy beam the reason is that when material fusing, consolidating and being frozen into solid block Volume contraction can occur for the region of powder material.In this regard, the height of melting range can be lower than the remainder of powder bed, Lead to that thicker layer of powder material can be deposited on the top in these regions during depositing next powder bed.In various embodiments In, it can determine the additional thickness of powder, and can increase to apply the energy of dusty material and be compensated fusing additional thickness Energy needed for powder increases.For example, this method may insure that each layer all melts completely, and reduce in 3-D building part Porosity.

In various embodiments, building part can be constructed based on object model, which can specify building part Intended shape.Object model can also include building part other desired characteristics, such as density, internal stress, melting it is complete Property etc..Before print procedure, during print procedure and/or after print procedure, the difference with object model can be determined.Example Such as, shrinking for actual implementation part can be by the way that actual implementation part and the object model of building part to be compared to determine.It shrinks It can result in the additional thickness of the powder deposited in next powder bed.For example, the additional thickness of the powder bed on constriction zone It can be determined based on through determining contraction.In certain embodiments, by sensing the shape of actual implementation part (for example, passing through Optical measurement) contraction can be determined in real time.It in certain embodiments, can be based on for example based on physics before print procedure Model shunk to determine, can should predict actual implementation by calculating thermal factor, gravity factor etc. based on the model of physics The shape of part.

In various embodiments, pass through compensation environment temperature, humidity, materials chemistry and granularity variation, laser intensity, thickness Difference in degree and neighbouring part geometry, may be implemented 3D printer accuracy and handling capacity is improved.

In various embodiments, 3D printer can print standardized test component/pattern, then can scan the standard Change test component/pattern for being compared with object model.It can measure and calculate the deviation and variance with geometric data. Then before starting printed product building part, the difference of printer capability can be compensated.

In various embodiments, the optics that building part can be executed before each layer of printing and after each layer of printing is swept It retouches.Monitoring system be can establish to scan powder bed after powder coating process and determine the distribution of dusty material.If deposited In the unlapped region of powder, then coating mechanism can be activated to coat the layer again.After scanning each layer by using Monitoring system, can be with application enhancements.Omit or occur what dusty material only partially melted if existed in the scanning of energy beam Region, then can be with activation energy beam to rescan these regions.

In various embodiments, high-resolution thermal imaging system can be used to create the closed loop for self calibration accuracy Feedback loop.High-resolution thermal imaging apparatus can monitor the shape for melting carrier during or dislocation exposure discontinuous in energy beam At.Feedback loop can compensate drift and the width of fusing carrier, to keep geometrical accuracy and print quality.Calibration sampling Piece (coupon) can be permanently attached to guarantee the accuracy of imaging system in building chamber.

Figure 1A-D illustrates the corresponding side view of the exemplary PBF system 100 during the different operational phases.As above Described, the specific embodiment illustrated in Figure 1A-D is one in many suitable examples using the PBF system of the principle of the disclosure A example.It is also to be noted that the element of other attached drawings in Figure 1A-D and the disclosure is not drawn necessarily to scale, but in order to Concept described herein is preferably illustrated, can draw greater or lesser.PBF system 100 may include can deposit it is each The depositor 101 of layer metal powder, can apply energy beam to melt (fuse) at the energy-beam source 103 that energy beam can be generated The deflector 105 of dusty material and the building plate 107 that one or more building parts (such as building part 109) can be supported. PBF system 100 can also include the building bottom plate 111 being placed in powder bed container.Powder bed wall of a container 112 usually limits Determine the boundary of powder bed container, which is clipped in a part building bottom plate of between wall 112 and adjacent lower section from side 111.Building bottom plate 111 can gradually decrease building plate 107, and depositor 101 is allowed to deposit next layer.Entire mechanism can To be present in the chamber 113 that can surround other components, to protect equipment, be able to carry out atmosphere and temperature adjusts and mitigates Pollution risk.Depositor 101 may include the funnel 115 for accommodating powder 117 (such as metal powder), and each layer can be made heavy The leveller 119 of the upper flat at accumulated powder end.

Referring in particular to Figure 1A, the figure shows after a piece of building part 109 has melted but next layer of powder PBF system 100 before deposition.In fact, to illustrate PBF system 100 deposited and melt multiple layers (such as 150 by Figure 1A Layer) in piece to be formed locating for the current state of (such as 150 pieces formed) building part 109 at the time of.Deposited is more A layer has created powder bed 121, which includes the powder for depositing but not melting.

Figure 1B is shown in the PBF system 100 at the next stage: wherein constructing bottom plate 111 can be by powder thickness 123 are spent to reduce.The reduction of building bottom plate 111 causes to construct part 109 and powder bed 121 passes through layer thickness 123 and declines, and makes The top that part and powder bed must be constructed reduces amount equal to layer thickness than the top of powder bed chamber wall 112.With this Mode, for example, can create on the top of building part 109 and powder bed 121 has equal with layer thickness 123 one Cause the space of thickness.

Fig. 1 C is shown in the PBF system 100 at the next stage: wherein depositor 101 is placed so that powder 117 to sink In space that is that product is created on building part 109 and the top surface of powder bed 121 and being defined by powder bed chamber wall 112. In this example, depositor 101 gradually moves on limiting space, while powder 117 is discharged from funnel 115.Leveller 119 The powder of release can be made smooth, to form the powder bed with the thickness for being substantially equal to layer thickness 123 (see Figure 1B) 125.Therefore, the powder in PBF system can be supported by dusty material support construction, which may include Such as building plate 107, building bottom plate 111, building part 109, wall 112 etc..It should be noted that the thickness of the powder bed 125 of diagram Degree (i.e. layer thickness 123 (Figure 1B)) is made greater than the example for being related to 150 previous sedimentaries above with reference to Figure 1A discussion Actual (real) thickness.

Fig. 1 D is shown in the PBF system 100 at the next stage: wherein after powder bed 125 (Fig. 1 C) deposition, Energy-beam source 103 generates energy beam 127 and deflector 105 applies energy beam so that a piece of melting under in building part 109.? In various exemplary embodiments, energy-beam source 103 can be electron beam source, and energy beam 127 constitutes electron beam in this case. Deflector 105 may include the deflecting plates that electric field or magnetic field can be generated, the electric field or magnetic field selectively deflect electron beam with Promote the inswept specified region to be melted of electron beam.In various embodiments, energy-beam source 103 can be laser, in this feelings Energy beam 127 is laser beam under condition.Deflector 105 may include optical system, which uses reflection and/or refraction It is selected to melt region to scan to carry out operating laser beam.

In various embodiments, deflector 105 may include one or more balance rings and actuator, the one or more Balance ring and actuator can rotationally and/or translationally energy-beam source energy beam is placed on appropriate location.In various embodiments, Energy-beam source 103 and/or deflector 105 can modulate energy beam, such as switch on and off energy beam when deflector scanning, make Energy beam is obtained to be applied only in the appropriate area of powder bed.For example, in various embodiments, energy beam can be by digital signal Manage device (DSP) modulation.

Fig. 2 illustrates the side view of exemplary sagging (sagging) in the PBF system that can result in overhanging regions deformation Figure.Fig. 2 shows building plates 201 and powder bed 203.It is building part 205 in powder bed 203.In order to be compared, dotted line is used Illustrate object model 207.In one embodiment, object model 207 includes being used as AM processor from what is created in CAD It inputs to render the data of the data model of building part.Object model 207 shows the intended shape of building part.In most numerical digit In setting, i.e., in the position not deformed, building part 205 is Chong Die with object model 207.Therefore, on 210 right side of pendency boundary In region, the solid line and the dotted superposition defined in object model 207 of characterization building part 205.However, in overhanging regions 209 Sagging deflections occur.In this example, overhanging regions 209 by top of each other melts multiple constitute.In this case, with Overhanging regions 209 from building part 205 main body in extend, deform it is more serious.

It should be noted that although melting does not occur directly on scattered powder, in region (in one of layer The adjacent edges of piece in powder layer below melt) in can also occur (deformation, higher residual stress etc.) certain A little problems.For example, can result in unexpected high temperature when the adjacent edges melted powder in following piece, this is because following Melted material is less, can not conduct by heat.The place of sharp edges is formed in following piece, these problems can be especially tight Weight.

Fig. 3 illustrates the exemplary PBF device 300 including closed-loop control.Fig. 3 show building plate 301, powder bed 303, And building part 305.Energy application system 309 can apply energy melt the dusty material in deposited powder layer.In order to Diagram, powder depositor are not shown in this figure.Energy application system 309 may include energy applicator 310, which applies Adding device 310 may include energy-beam source 311 and deflector 313.Energy application system can also include processor 314 and computer Memory 315 (random access memory (RAM), computer storage dish (such as hard disk drive, solid state drive) etc.). Memory 315 can store object model 316 and print command 317.Print command 317 may include in print procedure Each powder bed instruction, and the instruction can control energy-beam source 311 and how deflector 313 scans each powder bed. For example, print command 317 can control print parameters, sweep speed, beam power, the position of beam melting etc..Print command 317 can be determined by processor 314 based on object model 316.In other words, processor 314 can be by determining scanning speed Rate, beam power, beam melting position etc. generate print command 317, to form the every of building part 305 based on object model 316 It is a piece of.Energy applicator 310 receiving printing orders 317 and can apply energy beam from memory 315 with melted powder Material constructs part 305 to be based on print command creation.

PBF device 300 may include tokenizer 319, which obtains letter related with the melting of dusty material Breath.In this example, tokenizer 319 can be sensor 321, which can sense the shape about building part 305 Information.For example, sensor 321 may include optical sensor, such as camera.Sensor 321 can sense building part 305 Shape information 323 (such as dimensional measurements) and shape information can be sent to comparator 325.For example, passing through energy After amount application system 309 makes every a piece of melting of building part 305, sensor 321 can be in next layer of deposition of dusty material The shape of the part of sensing building before, and comparator 325 is sent to using the shape sensed as shape information 323.

Comparator 325 can obtain object model 316 from memory 315, and can execute object model and shape letter The comparison of breath 323 is with the determining difference with object model.For example, constructing certain parts of part 305 compared with object model 316 It is sagging.Comparator 325 can send different information to compensator 327.Compensator 327 can be modified based on the difference Print command 317.For example, being based on the difference, compensator 327 can be determined the area of the next powder bed thicker than rest layers Domain.Compensator 327 can modify print command 317 and be applied with increasing in scanning next time to the energy in thicker powder area Add, to ensure that the dusty material in thicker region is suitably melted.For example, compensator 327 can modify print command 317 With the beam power increased in thicker region and/or the sweep speed reduced in thicker region, more energy is applied to these Region.

In various embodiments, tokenizer 319 may include the edge of the marginal information of the dusty material after sensing melting Sensor.For example, melting problem frequently occurs in described edge or described adjacent edges.In these cases, Edge sensor can provide the advantageous information about described edge shape.In various embodiments, edge sensor can To sense the information at the edge of the dusty material after melting, shape, position, height etc..

In various embodiments, tokenizer may include the heat sensor for sensing thermal information, such as thermocouple, infrared sensing Device etc..In various embodiments, tokenizer may include optical sensor, such as camera.

Fig. 4 illustrates the exemplary PBF device 400 including feedforward control.Fig. 4 show building plate 401, powder bed 403, And building part 405.Energy application system 409 can apply energy so that the dusty material in deposited powder layer melts.In order to Diagram, powder depositor are not shown in this figure.Energy application system 409 may include energy applicator 410, the energy Applicator 410 may include energy-beam source 411 and deflector 413.Energy application system can also include processor 414 and calculate Machine memory 415 (RAM, computer storage dish etc.).Memory 415 can store object model 416 and print command 417.Print command 417 may include the instruction for powder bed each in print procedure, and the instruction can control energy How electron gun 411 and deflector 413 scan each powder bed.For example, print command 417 can control print parameters, such as sweep Retouch rate, beam power, position of beam melting etc..

In this example, print command 417 can be based on object model 416 by processor 414 and be based on physical model 418 To determine.Particularly, processor 414 may include tokenizer 419, which can obtain the melting with dusty material Related information.More particularly, tokenizer 419 can from memory 415 receiving printing orders 417 and can be by by object Reason modelling application determines the model 418 based on physics of building part 405 to print command.For example, tokenizer 419 can be held The software that row is stored in memory 415, which, which can be used physical modeling, predicts building part based on print command 417 Shape.The predicting shape for constructing part is the model 418 based on physics, is stored in memory 415.In this example, Fig. 4 It includes sagging at the fringe region of building part for illustrating the shape of the model 418 based on physics.It can pass through and be based on Fluid dynamics modeling is modeled the behavior of the dusty material after heating, is determined that Shu Jiare's is effective based on Thermodynamics modeling Property, modeled based on physical mechanics and to determine deposition due to dusty material and the power that generates is sagging to determine.

Therefore, according to the model 418 based on physics, if using the print command 417 being currently stored in memory 415 Building part is printed, then to construct part there will be hanging portion.However, print command 417 can be modified before print procedure It is sagging to eliminate or reduce.Particularly, the comparator 425 of processor 414 can receive object model 416 from memory 415 With the model 418 based on physics, and object model can be executed and based on the comparison of the model of physics with determining and object model Difference.In this way, comparator 425 can determine the certain of the model 418 compared with object model 416, based on physics Part is sagging.Comparator 425 can send different information to the compensator 427 of processor 414.Compensator 427 can be with Print command 417 is modified based on the difference.For example, being based on the difference, compensator 427 can be it is determined that according to based on object The model 418 of reason will apply less energy in sagging region.Compensator 427 can modify print command 417 to reduce The application of energy, sagging to prevent or reduce in these regions.For example, compensator 427 can modify print command 417, with Less energy is applied to by under by reducing the beam power in these regions and/or increasing the sweep speed in these regions Vertical region.In this way, for example, print command 417 can be modified based on the model based on physics before printing.

In various embodiments, the successive ignition of the above process can be executed.For example, modified print command 417 can To be fed back in tokenizer 419, tokenizer can determine the updated model based on physics, and comparator 425 can will more The model based on physics after new is compared with object model 416 and sends compensator 427 for updated difference, and Compensator can update modified print command.For example, until iteration can be continued until that variation is less than threshold tolerance.This When, modified print command 417 can be used for printing.

Energy applicator 410 can receive modified print command 417 from memory 415, and can be based on modification Print command afterwards applies energy beam and constructs part 405 with melted powder material to create.In this example of feedforward control, structure Part 405 is built with correct shape, this is because print command is modified before the printing.

Therefore, in the various embodiments using the model based on physics, one group can be created before print procedure and is beaten Print instruction.Tokenizer can determine the model based on physics based on original print command group before print procedure starts. Model based on physics can be compared by comparator with object model, to determine the difference between model.Compensator can be with Print command is modified to compensate difference, so that actual building part will be printed according to object model.In addition, in various embodiments In, the process for modifying print command can be iterative process, wherein the first modified print command group can be generated, it can be with base The model based on physics is updated in the first modified print command group, the updated model based on physics can be with object Model is compared, if any difference is greater than threshold tolerance, can determine the second modified print command group, and can be with The process is repeated until not having difference to be greater than threshold tolerance.

Fig. 5 illustrates the exemplary operation of comparator 500.Comparator 500 can receive object model from memory 502 501.Comparator 500 can also receive building information 503 from building information source 504 (memory, sensor etc.).Example Such as, building information 503 can be the information of the building part obtained by sensor, the shape letter of such as sensor 321 from Fig. 3 Breath.For example, building information 503 can be the information of the model (model 418 based on physics of such as Fig. 4) based on physics.Than It can be executed compared with device 500 and compare operation 505 to determine object model 501 and construct the difference between information 503.In this example In, compare operation 505 and determines difference 507 and difference 509.Difference 507 is to construct part to lack least a portion of space, it is, not Space including a part building part, although the space should include a part building part.Difference 509 be include additional building The space of part part, that is, the space including part building part, even if the space should not include part building part.It can incite somebody to action Difference 507 and 509 is sent to compensator 511 to determine the modification to print command.

In various embodiments, difference may include size, shape (such as deformation), integrality, the position of melting etc..? In various embodiments, tokenizer can sense the dusty material in the region of powder bed and be applied in the given time in energy beam Whether melted completely after to the dusty material in the region, and if dusty material melting is not exclusively after the predetermined time, Then compensator can modify print command so that additional energy to be applied to the dusty material in the region.For example, modified Print command may include the additional application of energy, for example, energy beam may return to endless after having scanned described The region of full-fusing.

In various embodiments, for example, building information may include melting after dusty material just at sagging one The sensor information of position in the layer.In this case, the powder bed when next layer of powder deposits, on sagging region Other regions than powder bed are thicker.Compensator can increase the powder material for being applied to and depositing on the sagging region of preceding layer The energy in region is expected, to ensure that the powder compared with thick-layer will melt completely.In this way, for example, the powder after melting can be used Sagging region is filled establishing height to desired level.

It in various embodiments, should the mould based on physics for example, building information may include the model information based on physics Type information can predict sagging region before generation is sagging.In such a case, it is possible to modify print command to prevent or subtract It is few sagging.For example, compensator can reduce the energy for being applied to dusty material region that can be sagging if applying higher energy Amount.In this way, for example, sagging compensation can be executed before generation is sagging.

In various embodiments, the model based on physics can characterize the dusty material after (such as due to evaporation) melting Loss.In various embodiments, the model based on physics can characterize the melting tank viscosity of the dusty material after melting.

In various embodiments, print command can be modified to compensate only for difference, which is the extra section for constructing part, Difference 509 above such as.For example, if a part building part raises upward to enter mean not include the space for constructing part It is interior, then can modify print command with it is a piece of under formation when less powder is melted on convex portion.

In various embodiments, print command can be modified to compensate only for difference, the difference be construct part lack part, Difference 507 above such as.For example, possibly can not then be corrected sagging if there is sagging and real-time compensation is used To mean do not include construct part space in part construct part.In such a case, it is possible to modify print command in shape More powder are melted when a piece of under in the space on sagging region, as shown in the example of following Fig. 6.With this side Formula for example, can correct building part lacks part, but is to maintain following hanging portion.Hanging portion can print It is removed after journey for example, by filing, sand milling etc..

Fig. 6 A-C illustrates the exemplary application of the energy of the powder bed using modified print command.Such as Fig. 6 A institute Show, PBF device 600 includes building plate 601, and building part 603 is formed in powder bed 605 on building plate 601.Powder bed 605 Including the powder bed 607 with desired layer thickness 609.A part of powder bed 607 has thicker layer thickness 611, the thicker layer thickness 611 is on the hanging portion of building part 603, and therefore than desired layer thickness 609 It is thicker.PBF device 600 further includes energy-beam source 613 and deflector 615.Modified print command 617 has been generated to compensate Construct the increase thickness of the powder bed 607 on the hanging portion of part 603.In this example, modified print command 617 is modified The beam power of energy-beam source 613.

Fig. 6 B illustrates a part of powder bed that will have thicker layer thickness 611 using modified beam power Powder melts in 607.Particularly, it in order to have the amount of powder layer 607 of thicker layer thickness 611 to melt, modifies 617 order energy-beam source 613 of print command afterwards increases beam power to realize more when scanning on the thicker portion in powder bed High-power energy beam 619.In this way, for example, more energy can be applied to has thicker layer thickness 611 Amount of powder layer 607, powder is melted completely.

Fig. 6 C is illustrated the powder melts in a part of powder bed 607 with desired layer thickness 609.This In the case of, modified print command 617 can order energy-beam source 613 reduce beam power, to realize lower power energy Beam 621, the lower power energy beam 621 can be for melting the powder with desired layer thickness 609 completely Beam power.

Fig. 7 is the flow chart for illustrating the illustrative methods of the closed loop compensation for PBF system.PBF system can be generated (701) energy beam and (702) energy beam can be applied carry out melted powder material to create the three-dimensional (3-D) with object model Object.PBF system can obtain (703) information related with the melting of dusty material.For example, information may include building part The sensor information (for example, deformation, sagging etc.) of shape, completeness of melting etc..PBF system can be determined based on information (704) with the difference of object model.For example, system can determine sagging if information instruction is sagging in a particular area Amount.PBF system can be applied based on energy of the information modification (705) to dusty material.For example, system can be based on it is sagging The information of amount increases the beam power of energy beam to melt the region of thicker powder completely.In various embodiments, energy is modified Application may include modification print command.In various embodiments, the application for modifying energy may include based on from one Or the feedback of multiple sensors comes real time modifying beam power, sweep speed etc..For example, temperature sensor can sense the beam position The temperature at place is set, the temperature is too low for fusing powder, and can increase beam power based on the temperature sensed.? In various embodiments, modifying applying for energy can be completed by modification for next layer of print command, for example, when detection When sagging into preceding layer, beam power can be increased for melting the powder in next layer on the hanging portion of preceding layer Melt.

The another exemplary that Fig. 8 A-C illustrates the energy of the powder bed using modified print command applies.Such as Fig. 8 A Shown, PBF device 800 includes building plate 801, and building part 803 is formed in powder bed 805 on building plate 801.Powder bed 805 include powder bed 807.A part of powder bed 807 is in overhanging regions 809.PBF device 800 further includes energy-beam source 813 With deflector 815.

In this example, (all as described above with reference to figure 4) feed forward process have been executed to determine modified printing Instruction 817, to compensate the sagging of generation when melting the powder bed 807 in overhanging regions 809.In this example, it modifies The beam scanning rate of deflector 815 is modified in print command 817 afterwards.

Fig. 8 B is illustrated will be in a part of powder bed 807 of overhanging regions 809 using modified beam scanning rate Powder melts.Particularly, in order to melt the amount of powder layer 807 in overhanging regions 809 in the case where not leading to sagging, Modified 817 order deflector 815 of print command increase beam scanning rate with realized when being scanned in overhanging regions 809 compared with The energy beam 819 of short scan.In this way, for example, less energy can be applied to the part powder in overhanging regions 809 Last layer 807 so that melting after powder do not have it is sagging.

Fig. 8 C is illustrated the powder melts in a part of powder bed 807 outside overhanging regions 809.In such case Under, modified print command 817 can order deflector 815 reduce beam scanning rate, with realize compared with slow scanning energy beam 821, the speed of the beam scanning for melting the powder not in overhanging regions should be can be compared with the energy beam 821 of slow scanning Rate.

Fig. 9 is the flow chart for illustrating the illustrative methods of the feedforward compensation for PBF system.PBF system can obtain (901) information related with the melting of dusty material.For example, the information may include the shape of prediction building part (for example, becoming Shape, sagging etc.), the model based on physics such as completeness of melting.PBF system can determine (902) and object mould based on information The difference of type.For example, system can determine sagging amount if the information prediction is sagging in a particular area.PBF system can To be applied based on energy of the information modification (903) to dusty material.For example, system can be based on the letter of the sag of chain of prediction It ceases sagging to prevent to increase the sweep speed of energy beam.In various embodiments, the application for modifying energy may include modification Print command.PBF system, which can be generated (904) energy beam and can apply (905) energy beam, carrys out melted powder material to create Build three-dimensional (3-D) object with object model.

Figure 10 A-E illustrates the exemplary PBF device 1000 with post-processing closed-loop control.Figure 10 A shows completion and beats PBF device 1000 after print operation.PBF device 1000 includes building plate 1001.The building of powder bed 1003 and the first completion Part 1005 is on building plate 1001.PBF device further includes energy application system 1007, which includes having Energy-beam source 1011 and the energy beam applicator 1009 of deflector 1013, the memory 1015 including object model 1017, printing Instruction 1019, comparator 1021 and compensator 1023.PBF device 1000 further includes object scan device 1025.

In this example, the first building part 1005 completed is the first building part printed based on object model 1017.Such as Shown in Figure 10 A, print command 1019 obtains object model 1017 from memory 1015, and print command is based on object mould Type.However, the first building part 1005 completed has the part of incorrect shape compared with object model 1017.Therefore, PBF device 1000 executes compensation program, as shown in Figure 10 B-E.

Figure 10 B illustrates the object scan program of PBF device 1000.Particularly, it is scanned by object scan device 1025 The first building part 1005 completed, to obtain the dimension information of the shape for the building part that first completes.Dimension information is as scanning Information 1027 is sent to comparator 1021.In addition, comparator 1021 receives object model 1017 from memory 1015.Comparator 1021 execute the comparison operation shown in Figure 10 C, to determine the difference between object model 1017 and scanning information 1027.

Figure 10 C illustrates the operation of comparator 1021.Comparator 1021 receives object model 1017 from memory 1015 And scanning information is received from object scan device 1025.The execution of comparator 1021 compares operation 1029 to determine object model Difference 1031 between 1017 and scanning information 1027 simultaneously sends compensator 1023 for the difference.

Figure 10 D illustrates the operation of compensator 1023.Compensator 1023 receives object model 1017 from memory 1015 And difference 1031 is received from comparator 1021.Compensator 1023 executes compensating operation 1033 with the compensated object mould of determination Type 1035.The print command generated from compensated object model 1035 will cause printing matched with object model 1017 Construct part.In other words, compensated object model 1035 is compensated for occurs when the building part 1005 that printing first is completed Error.Compensator 1023 sends compensated object model 1035 to be stored in memory 1015.

Figure 10 E illustrates the second building part completed printed using compensated object model 1035 1037.When the building part 1037 that printing second is completed, print command 1019 is based on compensated object model 1035.With this Mode, for example, the shape of the second building part 1037 completed can be matched with the shape of object model 1017.In fact, once Have determined that compensated object model 1035, each subsequent building part can be matched with the shape of object model 1017.

Figure 11 is the flow chart for illustrating the another exemplary method for the compensation of PBF system.PBF system can provide (1101) for printing the print command of 3-D object, and (1102) 3-D object can be printed based on the print command.Example Such as, which can print the first building part, the building part 1005 that first in such as Figure 10 A is completed.PBF system can sense (1103) at least part of shape in the 3-D object printed.For example, object scan device (such as object scan can be passed through Device 1025) scan the first building part.PBF system can be by the shape of the 3-D object of printing and reference figuration (such as object mould Type 1017) (1104) are compared to determine difference parameter, the size difference of such as shape.PBF system can be based on the difference Parameter updates (1105) print command.For example, print command can be based on the compensated object that can be determined by difference parameter Model (such as compensated object model 1035) Lai Gengxin.

Description before offer is to enable any person skilled in the art to practice various aspects described herein. Itd is proposed in the entire disclosure to the various modifications of these exemplary embodiments will be to those skilled in the art be easy it is aobvious and It is clear to.Therefore, claim is not limited to the exemplary embodiment proposed in entire disclosure, and is to fit to weigh with language Benefit requires consistent full scope.All structure and functions of element etc. of exemplary embodiment described in the entire disclosure Jljl is intended to by encompassed in the claims, and the element of exemplary embodiment described in the entire disclosure is for ability It is known or known later for the those of ordinary skill in domain.In addition, any content disclosed herein is all not intended to specially For the public, regardless of whether the disclosure is clearly described in the claims.Claim elements must not be according to 35U.S.C. § 112 (f) or applicable judicial power in the lawlike regulation of class to explain, unless clear using phrase " method being used for ... " The element is described, or in the case where claim to a method, describes the element using phrase " the step of being used for ... ".

Claims (16)

1. a kind of device for powder bed melting characterized by comprising

Powder bed fusing system comprising generate the energy-beam source of energy beam and apply the energy beam so that dusty material melts To create the deflector of three dimensional object based on object model；

Tokenizer obtains information related with the melting of the dusty material；

Comparator, based on the determining difference with the object model of the information；And

Compensator is applied based on energy of the difference modification to the dusty material.

2. the apparatus according to claim 1, which is characterized in that the compensator is additionally configured to by adjusting the energy The power of beam changes applied energy.

3. the apparatus according to claim 1, which is characterized in that the compensator is additionally configured to by adjusting the deflection The speed of device changes applied energy.

4. the apparatus according to claim 1, which is characterized in that the tokenizer includes the dusty material after sensing melting The edge sensor of marginal information, and the information includes the marginal information of the dusty material after the melting.

5. the apparatus according to claim 1, which is characterized in that the tokenizer includes the heat sensor for sensing thermal information, And the information includes the thermal information.

6. the apparatus according to claim 1, which is characterized in that the powder bed fusing system includes by the dusty material The depositor being deposited in multiple layers, and the deflector applies the energy beam to the powder in each layer of the layer Powder material is melted.

7. device according to claim 6, which is characterized in that the information include melting after dusty material in the layer First layer in position, and the compensator is additionally configured to be applied to the energy of the dusty material by increasing and change Become applied energy, the dusty material is deposited directly on the position in the second layer of the layer.

8. device according to claim 6, which is characterized in that the tokenizer is configured as sensing one in the layer Layer in region in dusty material in the given time the energy beam be applied to the dusty material in the region it Whether melt completely afterwards, and if the compensator to be configured as the dusty material not complete after the predetermined time Full-fusing then changes applied energy by the way that additional energy is applied to the dusty material in the region.

9. the apparatus according to claim 1, which is characterized in that the tokenizer includes optical sensor, and the letter Breath includes the optical information obtained from the optical sensor.

10. the apparatus according to claim 1, which is characterized in that the information includes the model based on physics.

11. device according to claim 10, which is characterized in that the model based on physics characterizes the powder after melting Powder material it is sagging, and the compensator be configured to compensate for it is described sagging.

12. device according to claim 11, which is characterized in that the powder bed fusing system includes depositing the powder The depositor of material, and it is described sagging by being caused due to the power for depositing the dusty material and generating.

13. device according to claim 10, which is characterized in that the model based on physics characterizes the powder after melting The loss of powder material, and the compensator is configured to compensate for the loss of the material after melting.

14. device according to claim 13, which is characterized in that the loss of the dusty material after melting is by evaporating Caused by.

15. device according to claim 10, which is characterized in that the model based on physics characterizes the powder after melting The melting tank viscosity of powder material, and the compensator is configured to compensate for the melting tank viscosity.

16. a kind of device for powder bed melting characterized by comprising

Adaptive controller provides the instruction for printing three dimensional object, data of the described instruction based on the three dimensional object Model；

Powder bed fusing system prints the three dimensional object based on described instruction；And

Feedback system is configured as sensing at least part of shape in printed three dimensional object, by what is sensed Shape is compared to determine difference parameter and update described instruction based on the difference parameter with reference figuration.